Osteoarthritis (OA) is the most common form of arthritis and the leading cause for disability in the United States, resulting in an extremely high socioeconomic burden. OA is clinically characterized by articular cartilage degeneration, subchondral bone sclerosis, and osteophyte formation. A variety of risk factors have been identified in the initiation and progression of OA including aging, obesity, traumatic injury, environmental factors and inherent genetic alterations. Despite extensive research to delineate the pathogenic mechanisms of OA, a complete understanding of the factors that initiate OA or accelerate its progression has yet to be achieved. Subsequently, there is no effective disease-modifying treatment for OA except pain relieving medication and surgical replacement of damaged joints.